1. Field of the Invention
The present invention relates to a retaining structure of a Liquid Crystal Display (LCD) panel and more particularly, to a retaining structure of an LCD panel used for electronic equipment on a mounting frame, which is able to absorb an applied shock while retaining the panel detachably.
2. Description of the Prior Art
FIG. 1 is an exploded diagram showing a conventional retaining structure of an LCD panel on a mounting frame.
In FIG. 1, an LCD panel 101 has a shape of an approximately rectangular plate. The panel 101 typically includes a pair of glass substrates (not shown), a spacer (not shown) located between the pair of substrates, and a liquid crystal (not shown) sandwiched between the pair of substrates. One of the pair of substrates usually has a set of pixel electrodes (not shown) and a plurality of switching transistors (not shown) arranged in a matrix array. Another of the pair of substrates usually has a set of common electrodes (not shown) and a color filter (not shown). The liquid crystal is sealed by the pair of substrates and the spacer.
A mounting frame 112 has a shape of a rectangular plate, which corresponds to the shape of the LCD unit 101. The frame 112 has a rectangular mounting surface 112b and four supporting members 112a fixed to the frame 112 at the respective corners of the surface 112b. The supporting members 112a protrude upward from the mounting surface 112b. Each of the members 112a has an L-shaped plan shape and covers a corresponding one of the corners of the frame 112.
A The frame 112 may be formed by an opaque synthetic-resin plate or a transparent synthetic-resin plate allowing to serve as a light-guiding plate for back light illumination to the LCD panel 101.
A Printed Wiring Board (PWB) 103 has a rectangular shape, which is larger than that of the LCD unit 101 and the mounting frame 112. The PWB 103 includes a controller circuitry (not shown) for controlling the LCD panel 101.
The LCD panel 101 is placed on the mounting surface 112b of the mounting frame 112. The panel 101 is simply placed onto the surface 112b and is not fixed thereonto. The panel 101, which is kept horizontally, is vertically inserted along the four supporting members 112a.
The height of the members 112a from the mounting surface 112b is larger than the total thickness of the LCD panel 101 and therefore, the top of the panel 101 is lower than the tops of the supporting members 112a when the panel 101 is placed on the mounting surface 112b. This height difference prevents an external pressure from being applied to the panel 101.
The combination of the mounting frame 112 and the LCD panel 101 mounted thereon is fixed onto a rectangular mounting surface 103b of the PWB 103 by a popular means. An opposite, lower surface to the mounting surface 112b of the frame 112 is contacted with the mounting surface 103b of the PWB 103.
With the conventional retaining structure of the LCD panel 101 shown in FIG. 1, the panel 101 is simply inserted into the rectangular space defined by the four supporting members 112a, and is not fixed onto the mounting frame 112. Therefore, the LCD panel 101 tends to be separated from the mounting frame 112 when the subsystem formed by the LCD panel 101, the mounting frame 112, and the PWB 103 is built or incorporated into a casing or envelope (not shown).
As a result, there is a problem that the building/incorporating operation or work for the subsystem is difficult to be performed.
Further, when the LCD panel 101 is applied with a shock due to falling and/or impact of the subsystem, the panel 101 tends to collide with some of the supporting members 112a. This causes another problem that the panel 101 is readily damaged and/or broken.
FIG. 2 is an exploded diagram showing another conventional retaining structure of an LCD panel on a mounting frame, in which an adhesive layer 104 is additionally provided between the LCD panel 101 and the mounting frame 112.
The panel 101 is fixed onto the mounting surface 112b of the frame 112 by the adhesive layer 104, thereby preventing the panel 101 from being shifted with respect to the frame 112 and being separated from the frame 112.
With the conventional retaining structure of the LLCD panel 101 shown in FIG. 2, since the LCD panel 101 is fixed onto the mounting frame 112 by the adhesive layer 104, the shift and separation of the LCD panel 101 are able to be prevented during the building or incorporating operation of the subsystem.
However, in this case, there is a problem that the LCD panel 101 is unable to be replaced with another one even if some error takes place in the panel 101.
Additionally, when the mounting frame 112 has a function of a light-guiding plate for back light illumination, there arises a problem that some brightness unevenness of the back light tends to occur due to the adhesive layer 104.